From e6472ff46cbed97c2a238a8ef7d321351931333a Mon Sep 17 00:00:00 2001 From: Brijesh Singh Date: Thu, 30 May 2024 06:16:30 -0500 Subject: [PATCH 070/100] hw/i386/sev: Add function to get SEV metadata from OVMF header RH-Author: Paolo Bonzini RH-MergeRequest: 245: SEV-SNP support RH-Jira: RHEL-39544 RH-Acked-by: Thomas Huth RH-Acked-by: Bandan Das RH-Acked-by: Vitaly Kuznetsov RH-Commit: [70/91] ba818dade96119c8a51ca1fb222f4f69e2752396 (bonzini/rhel-qemu-kvm) A recent version of OVMF expanded the reset vector GUID list to add SEV-specific metadata GUID. The SEV metadata describes the reserved memory regions such as the secrets and CPUID page used during the SEV-SNP guest launch. The pc_system_get_ovmf_sev_metadata_ptr() is used to retieve the SEV metadata pointer from the OVMF GUID list. Signed-off-by: Brijesh Singh Signed-off-by: Michael Roth Signed-off-by: Pankaj Gupta Message-ID: <20240530111643.1091816-19-pankaj.gupta@amd.com> Signed-off-by: Paolo Bonzini (cherry picked from commit f3c30c575d34122573b7370a7da5ca3a27dde481) Signed-off-by: Paolo Bonzini --- hw/i386/pc_sysfw.c | 4 ++++ include/hw/i386/pc.h | 26 ++++++++++++++++++++++++++ target/i386/sev-sysemu-stub.c | 4 ++++ target/i386/sev.c | 32 ++++++++++++++++++++++++++++++++ target/i386/sev.h | 2 ++ 5 files changed, 68 insertions(+) diff --git a/hw/i386/pc_sysfw.c b/hw/i386/pc_sysfw.c index ac88ad4eb9..9b8671c441 100644 --- a/hw/i386/pc_sysfw.c +++ b/hw/i386/pc_sysfw.c @@ -260,6 +260,10 @@ void x86_firmware_configure(void *ptr, int size) pc_system_parse_ovmf_flash(ptr, size); if (sev_enabled()) { + + /* Copy the SEV metadata table (if it exists) */ + pc_system_parse_sev_metadata(ptr, size); + ret = sev_es_save_reset_vector(ptr, size); if (ret) { error_report("failed to locate and/or save reset vector"); diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h index 3f53ec73ac..94b49310f5 100644 --- a/include/hw/i386/pc.h +++ b/include/hw/i386/pc.h @@ -167,6 +167,32 @@ void pc_acpi_smi_interrupt(void *opaque, int irq, int level); #define PCI_HOST_ABOVE_4G_MEM_SIZE "above-4g-mem-size" #define PCI_HOST_PROP_SMM_RANGES "smm-ranges" +typedef enum { + SEV_DESC_TYPE_UNDEF, + /* The section contains the region that must be validated by the VMM. */ + SEV_DESC_TYPE_SNP_SEC_MEM, + /* The section contains the SNP secrets page */ + SEV_DESC_TYPE_SNP_SECRETS, + /* The section contains address that can be used as a CPUID page */ + SEV_DESC_TYPE_CPUID, + +} ovmf_sev_metadata_desc_type; + +typedef struct __attribute__((__packed__)) OvmfSevMetadataDesc { + uint32_t base; + uint32_t len; + ovmf_sev_metadata_desc_type type; +} OvmfSevMetadataDesc; + +typedef struct __attribute__((__packed__)) OvmfSevMetadata { + uint8_t signature[4]; + uint32_t len; + uint32_t version; + uint32_t num_desc; + OvmfSevMetadataDesc descs[]; +} OvmfSevMetadata; + +OvmfSevMetadata *pc_system_get_ovmf_sev_metadata_ptr(void); void pc_pci_as_mapping_init(MemoryRegion *system_memory, MemoryRegion *pci_address_space); diff --git a/target/i386/sev-sysemu-stub.c b/target/i386/sev-sysemu-stub.c index 96e1c15cc3..fc1c57c411 100644 --- a/target/i386/sev-sysemu-stub.c +++ b/target/i386/sev-sysemu-stub.c @@ -67,3 +67,7 @@ void hmp_info_sev(Monitor *mon, const QDict *qdict) { monitor_printf(mon, "SEV is not available in this QEMU\n"); } + +void pc_system_parse_sev_metadata(uint8_t *flash_ptr, size_t flash_size) +{ +} diff --git a/target/i386/sev.c b/target/i386/sev.c index e84e4395a5..17281bb2c7 100644 --- a/target/i386/sev.c +++ b/target/i386/sev.c @@ -597,6 +597,38 @@ SevCapability *qmp_query_sev_capabilities(Error **errp) return sev_get_capabilities(errp); } +static OvmfSevMetadata *ovmf_sev_metadata_table; + +#define OVMF_SEV_META_DATA_GUID "dc886566-984a-4798-A75e-5585a7bf67cc" +typedef struct __attribute__((__packed__)) OvmfSevMetadataOffset { + uint32_t offset; +} OvmfSevMetadataOffset; + +OvmfSevMetadata *pc_system_get_ovmf_sev_metadata_ptr(void) +{ + return ovmf_sev_metadata_table; +} + +void pc_system_parse_sev_metadata(uint8_t *flash_ptr, size_t flash_size) +{ + OvmfSevMetadata *metadata; + OvmfSevMetadataOffset *data; + + if (!pc_system_ovmf_table_find(OVMF_SEV_META_DATA_GUID, (uint8_t **)&data, + NULL)) { + return; + } + + metadata = (OvmfSevMetadata *)(flash_ptr + flash_size - data->offset); + if (memcmp(metadata->signature, "ASEV", 4) != 0 || + metadata->len < sizeof(OvmfSevMetadata) || + metadata->len > flash_size - data->offset) { + return; + } + + ovmf_sev_metadata_table = g_memdup2(metadata, metadata->len); +} + static SevAttestationReport *sev_get_attestation_report(const char *mnonce, Error **errp) { diff --git a/target/i386/sev.h b/target/i386/sev.h index 5dc4767b1e..cc12824dd6 100644 --- a/target/i386/sev.h +++ b/target/i386/sev.h @@ -66,4 +66,6 @@ int sev_inject_launch_secret(const char *hdr, const char *secret, int sev_es_save_reset_vector(void *flash_ptr, uint64_t flash_size); void sev_es_set_reset_vector(CPUState *cpu); +void pc_system_parse_sev_metadata(uint8_t *flash_ptr, size_t flash_size); + #endif -- 2.39.3